Add support for simplified and traditional Chinese

[benoit74]

Changes

• scraper --language parameter now accepts zh-hans and zh-hant values
• these two values are mapped to proper values for both the ZIM Language metadata (both zho) and the proper curriculum path on FCC repo
• scraper --name and --zim-file parameter are kept untouched

[codecov]

Codecov Report

❌ Patch coverage is 60.00000% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 40.77%. Comparing base (8b73ead) to head (4a60d00).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
scraper/src/fcc2zim/scraper.py	50.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #135      +/-   ##
==========================================
+ Coverage   40.66%   40.77%   +0.10%     
==========================================
  Files           9        9              
  Lines         359      363       +4     
  Branches       52       53       +1     
==========================================
+ Hits          146      148       +2     
- Misses        209      210       +1     
- Partials        4        5       +1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.